title: Activation of the yeast cell wall integrity MAPK pathway by zymolyase depends on protease and glucanase activities and requires the mucin-like protein Hkr1 but not Msb2.
abstract: Yeast adaptation to conditions in which cell wall integrity is compromised mainly relies on the cell wall integrity (CWI) mitogen-activated protein kinase (MAPK) pathway. Zymolyase, a mixture of cell wall-digesting enzymes, triggers a peculiar signaling mechanism in which activation of the CWI pathway is dependent on the high-osmolarity glycerol MAPK pathway. We have identified inhibitors of the principal enzyme activities present in zymolyase and tested their effect on the activation of the MAPK of the CWI pathway, Slt2/Mpk1. Eventually, only β-1,3-glucanase and protease activities were essential to elicit Slt2 activation and confer lytic power to zymolyase. Moreover, we show that the osmosensor Hkr1 is required for signaling, being the most upstream element identified to date.
authors.affiliation: Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, IRYCIS, 28040 Madrid, Spain. Electronic address: josemanu@farm.ucm.es.
authors.forename: José M
authors.initials: JM
authors.lastname: Rodríguez-Peña
authors.forename: Sonia
authors.initials: S
authors.lastname: Díez-Muñiz
authors.forename: Clara
authors.initials: C
authors.lastname: Bermejo
authors.forename: César
authors.initials: C
authors.lastname: Nombela
authors.forename: Javier
authors.initials: J
authors.lastname: Arroyo
mesh_terms: D002473:Cell Wall / Q000378:metabolism*; D002688:Chitinases / Q000737:chemistry; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000737:chemistry*; D006026:Glycoside Hydrolases / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D008565:Membrane Proteins / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: C512735:HKR1 protein, S cerevisiae; D047908:Intracellular Signaling Peptides and Proteins; C076360:MSB2 protein, S cerevisiae; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; D006026:Glycoside Hydrolases; D002688:Chitinases; D004693:Glucan Endo-1,3-beta-D-Glucosidase; D010447:Peptide Hydrolases
keywords: 3,4-dichloroisocoumarin; ACZ; CWI; CWI pathway; Cell wall; DCI; EDTA; GL; MAPK; Stress; Yeast; Zymolyase; acetazolamide; cell wall integrity; ethylenediaminetetraacetic acid; mitogen activated protein kinase; δ-gluconolactone